Compact radiation generators, such as pulsed neutron generators and x-ray generators, are useful for well logging applications. A typical radiation generator includes a charged particle source, an acceleration column, and a target. In operation, such a radiation generator generates charged particles with the charged particle source, focuses the charged particles into a beam, then accelerates the beam toward and into the target using the acceleration column. When the charged particles of the beam strike the target, radiation, such as neutron or x-ray radiation, is generated. This radiation is emitted or directed into an oil formation from within a borehole, and interacts with constituents of the oil formation, which ultimately generates formation sourced radiation. A well logging tool equipped with suitable radiation detectors can detect the formation sourced radiation, and determine properties of the formation based thereupon.
There are many operating parameters and conditions of such compact radiation generators that can affect performance, consistency of radiation output, and the service life of the compact radiation generator. One such operating parameter is whether the beam is properly focused. If the beam is not properly focused, various reactions can occur which can negatively impact the operation of the compact radiation generator. Therefore, new ways of maintaining proper beam focus are desired.